Need some help with a weird leak problem on my Brocock XR.

[PewPew28]

Hello all,

Hope there is some Brocock masters in these threads today. My issue is every time I fill my Ranger XR (200 bar) she leaks down to around 150 bar, and then stops leaking. Any ideas on the issue?
She is only 4-5 months old, this was the first time shooting her, only 2 magazines through her by me. After that initial time shooting to sight her in is when I noticed the problem. Tried refilling a few times but same result of leaking to 150 bar. I cannot find any Videos on the disassembly or reassembly of this gun so its kept me from trying a fix myself. If someone can point me towards a breakdown video that would be great. If you have any ideas of what could be wrong I would love to hear them, or point me towards someone that can help. I will be checking back here a few times a day so feel free to ask any questions that may help solve my issue. Thanks Guys and Gals I truly appreciate it.

photos attached (until I figure out how to post pictures in the post)

[woogie_man]

How are you filling the rifle?

If by a tank, how fast are you filling the rifle?  You could simply be filling to fast and are causing to much heat in the rifle tank. 
Where are you filling the rifle?  Inside and then going out?  Because a temperature change will cause you to loose pressure as well.
Are you sure the rifle is actually leaking, if it is can you find out where the leak is coming from?  Put a balloon on the muzzle, and spray the rifle with soapy water to find any leaks.

I am sure it is a simple fix if it is something.

[PewPew28]

Filled by machine, filled inside and then stayed inside, its a small tank like 80cc irc.